Making an electrical apparatus more efficient has been desired strongly, and a further achievement of lower core loss has been required for a non-oriented electrical steel sheet used for an iron core material of a motor contained in an electrical apparatus. Then, there have been studied a technique of containing Si, Al, and so on in a non-oriented electrical steel sheet to increase resistivity and increase a grain diameter, a technique of adjusting hot-rolled sheet annealing and a cold rolling ratio to thereby improve texture, and so on.
Further, a non-oriented electrical steel sheet is an electrical steel sheet having random crystal orientations in the direction parallel to its surface, but depending on the use of a non-oriented electrical steel sheet, there is also sometimes a case that one having a magnetic property in one direction parallel to its surface, for example, a rolling direction more excellent than that in the other direction is preferable. For example, in the case when a divided core is used as a stator of a motor, the electrical steel sheet as described above is preferably used for the divided core. As an electrical steel sheet having an excellent magnetic property in the rolling direction, a grain-oriented electrical steel sheet is also considered, but a glass coating film exists on surfaces of the grain-oriented electrical steel sheet, so that punching is difficult to be performed. Further, as compared to the non-oriented electrical steel sheet, more controls are required for manufacturing the grain-oriented electrical steel sheet, and the grain-oriented electrical steel sheet is expensive. Incidentally, in the case of the divided core being used as a stator of a motor, the direction of easy magnetized of the electrical steel sheet is allowed to agree with the direction in which the magnetic flux flows, and thus the efficiency of the motor can be improved. Further, it is possible to improve the yield of the electrical steel sheet being a material and to increase a winding filling factor.
Various proposals regarding the non-oriented electrical steel sheet for a divided core have been made. However, in conventional techniques, it is difficult to obtain the sufficient magnetic property in the rolling direction.